A to Z of MS
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A to Z of MS Natalizumab (Tysabri)
Product names
Tysabri
Natalizumab is a disease modifying drug licensed for use with people with highly active relapsing remitting multiple sclerosis (two or more disabling relapses in one year). Studies have shown natalizumab reduces the occurrence of relapse by around two thirds and significantly reduces the rate of disease progression.
During development the drug was known as Antegren.
How natalizumab works
Natalizumab is a type of drug called monoclonal antibodies. Natalizumab binds to molecules on the surface of specific immune cells and it is thought to act by preventing the cells from passing into the central nervous system via the blood-brain barrier.
How is natalizumab given?
Natalizumab is taken as an intravenous (IV) infusion via a drip once every four weeks.
Side effects and contraindications
Natalizumab should not be taken in conjunction with other immune suppressing drugs. This followed reports of two cases of progressive multifocal leukoencephalopathy (PML) a rare demyelinating disorder of the central nervous system during research studies. A number of further cases of PML have been identified since the drug was licensed and the manufacturers estimate the risk to be between one and two cases in a thousand.
In January 2010 the European Medicines Agency completed a review of natalizumab that found that the risk of PML increases after two years of treatment although this risk remains low and the benefits of the drug continue to outweigh its risks.
Commonly reported side effects of natalizumab include dizziness, nausea, urticaria (a skin rash) and stiffness. Natalizumab may increase chances of getting an unusual or serious infection.
References
Polman CH, et al.
A randomized, placebo-controlled trial of natalizumab for relapsing multiple sclerosis.
New England Journal of Medicine 2006; 354(9): 899-910.
abstract
Rudick RA, et al.
Natalizumab plus interferon beta-1a for relapsing multiple sclerosis.
New England Journal of Medicine 2006; 354(9): 911-923.
abstract
European Medicines Agency recommends additional measures to better manage risk of progressive multifocal leukoencephalopathy (PML) with Tysabri.
European Medicines Agency press release - 21 January 2010.
read pdf (69kb)
Patient Information Leaflet
- Tysabri (EMC website)
- Webcast on drug therapy
- Neurologist Prof David Bates addresses some of the questions people ask about disease modifying drugs
- Watch the webcast